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Introduction to the Autosampler
Sampling Sequence
Injection Sequence
Before the start of the injection sequence, and during an analysis, the
injection valve is in the mainpass position (Figure 34). In this position, the
mobile phase flows through the autosamplers metering device, sample
loop, and needle, ensuring all parts in contact with sample are flushed
during the run, thus minimizing carry-over
Figure 31 Mainpass Position
When the sample sequence begins, the valve unit switches to the bypass
position (Figure 32). Solvent from the pump enters the valve unit at port 1,
and flows directly to the column through port 6.
Figure 32 Bypass Position